The present invention relates to optical systems, and more particularly, to methods and apparatus for creating and capturing perceivable 3-D images of an object and constructing 3-D models of the object that can be viewed and measured from any angle.
Based on the state of the art prior to the present invention, the creation of a viewable 3-D image of an object in an optical system, such as a microscope, requires the use of filters, dual imaging systems or expensive viewing optics, all of which have their known disadvantages. The prior art has used the notion of convergence parallax or stereoscopic viewing from two angles simultaneously. In the present invention, we teach the use of motion parallax to create a perceivable 3-D image.
Prior to the present invention, it has not been possible to view an object in real-time 3-D through a standard microscope by the addition of a relatively inexpensive add-on device or to create a tomographic model of an object using such a device.
The present invention teaches methods and apparatus for obtaining 3-D images of an object in a standard microscope by continuously changing the angle from which the image of the object is viewed. xe2x80x9cViewxe2x80x9d, xe2x80x9cviewingxe2x80x9d and xe2x80x9cviewedxe2x80x9d as used throughout this specification refer to detection of an image by either the human eye or an optical or electronic device or system.
A typical optical system for creating the image of an object, such as a microscope, includes one or more aperture planes conjugate to the objective lens aperture, such as the condenser lens aperture, the light source of the system, the eye-point of the eyepiece (or barlow lens) or any conjugate relayed aperture plane that uses relay lenses. When used herein, xe2x80x9cobjective aperturexe2x80x9d refers to the objective lens aperture and any aperture at a plane conjugate to the objective lens aperture.
The present invention teaches that by selecting an objective aperture in either the illumination path or the viewing path of a light transmitting optical system and continuously changing the portion of that objective aperture through which the light passes, motion parallax is created. To the viewer, the image of the object is continuously moving in a way that makes the foreground elements of the image distinguishable from the background elements. In this way, the image appears to the viewer in 3-D without the need for any viewing aids, such as special 3-D spectacles or filters. In fact, with the present invention, 3-D perception is even created in microscopes having only a monocular viewing head.
When the portion of the selected objective aperture that passes light is continuously changed, as, for example, by rotating an off-centered opaque mask having an aperture (mask aperture) at an objective aperture, the image of the object will appear to move in an inclined rotary motion, distinguishing the elements of the image in the foreground from those in the background.
If the portion of the selected objective aperture that passes light is continuously changed by a back and forth motion of a mask aperture in the y-axis, then the image appears to rock back and forth. If the back and forth motion is in the x-axis, then the image will appear to roll from left to right.
The shape of the moving mask aperture will determine image properties, such as depth of field, definition (highlighting and shadowing effects), contrast, resolution and parallax angle differences. The present invention provides for control of image properties by selecting different shapes and sizes for dynamic mask apertures. The dynamic mask apertures can be physical openings in otherwise opaque members or other means of occluding light, such as LCD shutter mechanisms, and can be inserted or removed from the light path as required.
In addition to a dynamic mask aperture for continuously changing the portion of a selected objective aperture that passes light, the advantages of the present invention are also achieved by continuously moving a shaped light beam at a selected objective aperture so that the portion of the aperture which passes light is continuously changed. A xe2x80x9cshaped beamxe2x80x9d as used herein means a light beam that is shaped such that it fills less than the entire objective aperture and as used herein includes, without limitation, masked beams, focused beams and an array of light-emitting diodes (LEDs). By locating an array of LEDs at an objective aperture (such as a condenser lens aperture) and stimulating different ones of the LEDs in a timed sequence, it is possible, using known techniques, to continuously change the portion of the objective aperture that passes light. In such a case, the LED array is both the shaped beam and the light source.
Regardless of the particular motion generated or the particular structures used to continuously change the portion of a selected objective aperture that passes light, the continuously moving image created distinguishes the relative positions of the elements of the object and the object can be detected in 3-D by continuously interrogating the object from different points of view.
When the objective aperture is in the illumination part of the system, the benefits of oblique illumination are also imparted to the image.
Because the invention can be applied to an objective aperture in either the illumination or viewing paths of an optical system, the present invention is useful in systems using transmitted illumination, reflection illumination or florescence.
The present invention permits the creation of a series of discrete, obliquely angled images at particular locations throughout the object. Such a series of images can be digitized and analyzed by a computer program that will create an accurate three-dimensional model of the object that can be viewed and measured from any angle. Thus, the invention, when combined with an optical viewing system, constitutes the hardware portion of a tomographic microscope.
It is an object of the present invention to create a 3-D image of an object in an optical system without the use of viewing aides, such as special spectacles or the like.
It is an object of the present invention to create a viewable 3-D image of an object in an optical system by creating motion parallax.
It is another object of the invention to create motion parallax in an optical system for creating a 3-D image of an object by continuously changing the portion of an objective aperture through which light passes.
A further object of the present invention is to create a series of images of an object that can be digitized and analyzed by a computer program that will create an accurate three-dimensional model of the object that can be viewed and measured from any angle.